Antibiotics (Oct 2024)

Validation of Recombinase Polymerase Amplification with In-House Lateral Flow Assay for <i>mcr-1</i> Gene Detection of Colistin Resistant <i>Escherichia coli</i> Isolates

  • Naeem Ullah,
  • Nutchaba Suchanta,
  • Umaporn Pimpitak,
  • Pitak Santanirand,
  • Nutthee Am-In,
  • Nuntaree Chaichanawongsaroj

DOI
https://doi.org/10.3390/antibiotics13100984
Journal volume & issue
Vol. 13, no. 10
p. 984

Abstract

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Background/Objectives: The emergence of the mobilized colistin resistance 1 (mcr-1) gene, which causes colistin resistance, is a serious concern in animal husbandry, particularly in pigs. Although antibiotic regulations in many countries have prohibited the use of colistin in livestock, the persistence and dissemination of this plasmid-mediated gene require effective and rapid monitoring. Therefore, a rapid, sensitive, and specific method combining recombinase polymerase amplification (RPA) with an in-house lateral flow assay (LFA) for the mcr-1 gene detection was developed. Methods: The colistin agar test and broth microdilution were employed to screen 152 E. coli isolates from pig fecal samples of five antibiotic-used farms. The established RPA-in-house LFA was validated with PCR for mcr-1 gene detection. Results: The RPA-in-house LFA was completed within 35 min (20 min of amplification and 5–15 min on LFA detection) at 37 °C. The sensitivity, specificity, and accuracy were entirely 100% in concordance with PCR results. No cross-reactivity was detected with seven common pathogenic bacteria or other mcr gene variants. Conclusions: Therefore, the in-house RPA-LFA serves as a point-of-care testing tool that is rapid, simple, and portable, facilitating effective surveillance of colistin resistance in both veterinary and clinical settings, thereby enhancing health outcomes.

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